The present application relates generally to electrical connectors, and specifically to weatherproof connectors for coaxial cables.
Coaxial connections are widely used to conduct radio frequency signals with little electromagnetic interference from other signals and with minimal power losses when installed next to metal objects. The low vulnerability of coaxial cable to power losses and interference is due to the containment of the magnetic field carrying the signal to a space between an inner conductor surrounded by a tubular insulating layer, surrounded by a tubular conducting shield. Electric and magnetic fields outside the cable are largely kept from interfering with signals inside the cable. To confer these advantages and function as a transmission line, the dimensions of the cable must be controlled to give a precise, constant conductor spacing. Larger diameter cables and cables with multiple shields have less leakage. This property makes coaxial cable a good choice for carrying weak signals that cannot tolerate interference from the environment or for stronger electrical signals that must not be allowed to radiate or couple into adjacent structures or circuits. Common applications of coaxial cable include video, television and radio transmission, and computer data connections.
However, the functionality of coaxial cable depends on the integrity of its structure. For example, any contact at all between the conducting shield and the inner conductor will cause a short circuit, causing complete signal loss. This most often occurs at damaged or improperly installed end connectors and splices. Also, the connector or splice must be properly attached to the shield, as this provides the path to ground the interfering signal.
Consequently, it is important to protect coaxial connections from damage and improper installation. This is especially true in the outdoor environment, where omnipresent moisture can penetrate the connection and enter the cable. It is of course most critical in a submerged environment. Moisture can corrode the cable parts, and also close or short a circuit between the inner connector and the conducting shield. Attempts have been made to develop waterproof coaxial connectors. However, to date all such connectors require the assembly of multiple parts and the use of specialized tools to establish a reliable and waterproof connection. This is a severe disadvantage, as coaxial connections must often be installed outdoors in places that are difficult or dangerous to access.